1. Field of the Invention
The present invention is particularly adapted for use in high temperature wells where steam is injected into an underground formation to enhance the recovery of hydrocarbons. The present invention can also be used in high pressure/high temperature geothermal wells.
2. Description of the Prior Art
For many years packers have been used to provide a seal between a tubing string and a casing string within a well bore. Generally, formation fluids enter the bore of the casing string below the packer and are directed to flow to the well surface through the tubing string by the packer. Thus, the casing above the packer is protected from the formation fluids. Also, the well is easier to control by confining the formation fluids to the tubing string.
The use of packers and tubing is even more important while injecting high temperature and pressure steam into a hydrocarbon formation or in recovering energy from deep geothermal wells. U.S. Pat. Nos. 3,330,357 and 3,385,366 to T. L. Elliston show packers using asbestos rings to form a seal under high temperature conditions. U.S. Pat. No. 4,050,517 discloses flexible seals to compensate for the high temperatures found in geothermal wells.
Pending U.S. Patent Application Ser. No. 961,139 to Joseph L. Pearce et al discloses using elastomeric material reinforced with wire mesh in pumpdown piston elements. The reinforced elastomeric material displays markedly improved wear characteristics while the pumpdown element is moving through a well conduit. Various patents cited in this application, including U.S. Pat. No. 2,143,106 to A. L. Freedlander, disclose reinforcing elastomeric material with metal for use in oil and gas wells.
None of these patents show nor teach a packer having a sealing unit or anchoring means in accordance with the present invention.